The big news in the Silverlight developer world today is the release of Prism v2 (also called the Composite Application Guidance). So what is this?

Prism guidance is a set of tools, samples, references and written guidance to help you more easily build modular applications. Generally the “modular” application will feature several screens, flexible user interaction and role-based behavior. Composite applications using these patterns are meant to be loosely coupled and contain independently evolving pieces that can work together. So in the Prism 2 release you are provided:

Composite Application Library

Reference Implementation (Stock Trader application)

9 Quick starts

26 How-to’s

Documentation and written guidance on the UI patterns and client architectures you may face

There has been much talk about the Model-View-ViewModel (MVVM) pattern for Windows Presentation Foundation (WPF)and Silverlight development. The Prism release adapts this model (refers to this as the presentation modelto match what some other pattern documentation in the greater technology world uses) in the reference implementation of the Stock Trader application.

NOTE: The Stock Trader application is a reference implementation of the composite application guidance. It isn’t meant to actually server real stock trading, but was inspired by those similar scenarios.

Prism 2 is an evolution from a July 2008 release that was primarily for WPF applications. This new release brings updates and those concepts to Silverlight, including an implementation of commanding in Silverlight as well as demonstration of the use of input validation using these concepts.